WATER-STRESS AND TREE PHENOLOGY IN A TROPICAL DRY FOREST IN THE LOWLANDS OF COSTA-RICA
WATER-STRESS AND TREE PHENOLOGY IN A TROPICAL DRY FOREST IN THE LOWLANDS OF COSTA-RICA
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DOI：
10.2307/2260006
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发表时间：
1984-01-01
影响因子：
5.5
通讯作者：
BORCHERT, R
中科院分区：
文献类型：
--
作者：
REICH, PB;BORCHERT, R
在水分胁迫的物候和季节变化，所示的周长的变化，监测1年在许多树木的12种。[加勒比合欢，Astronium graveolens，Bursera simaruba，Cochlospermum vitifolium，Cordia alliodora，Enterolobium cyclocarpum，Guazuma tomentosa，Licania arborea，Lonchocarpus minimiflorus，Lysiloma lysannii，Spondias purpurea，Tabebuia rosea]生长在哥斯达黎加瓜纳卡斯特热带低地落叶林的干燥和潮湿地点。在干旱地区，树木经历了水分胁迫，在旱季早期落叶。在大多数物种中，再水化，然后是萌芽，只发生在沉重的干旱之后。在一些物种中，在持续干旱期间，叶子脱落之后是复水和芽断裂。在芽延伸，这很少持续超过几个星期，树木经历了水分胁迫，尽管在潮湿的土壤中生长。在潮湿的网站，树木经历很少或没有明显的水分胁迫，他们保持万年青或迅速交换叶片在旱季。一般来说，落叶和萌芽的时间，在许多物种中，开花在很大程度上取决于树木水分状况的变化。反过来，这些现象是环境水分状况与树木结构和功能状态之间相互作用的结果。有时，树木的功能状态会抵消环境的影响;在潮湿的季节，长出新枝的树木会暂时缺水，而在干旱的季节，裸露的树木会重新补充水分。树木生长的季节性格局与树木水分状况的季节性变化有很高的相关性，但仅与环境水分有效性有间接关系。没有证据表明树木的发育受光周期或温度季节变化的控制。
Phenology and seasonal variations in water stress, as indicated by variations in girth, were monitored for 1 yr in numerous trees of 12 spp. [Albizzia caribaea, Astronium graveolens, Bursera simaruba, Cochlospermum vitifolium, Cordia alliodora, Enterolobium cyclocarpum, Guazuma tomentosa, Licania arborea, Lonchocarpus minimiflorus, Lysiloma seemannii, Spondias purpurea, Tabebuia rosea] growing at dry and moist sites in a tropical lowland deciduous forest in Guanacaste, Costa Rica. At dry sites, trees experienced water stress and shed their leaves early in the dry season. In most species, rehydration, followed by bud break, took place only after heavy rainfalls. In some species, leaf shedding was followed by rehydration and bud break during continuing drought. During shoot extension, which rarely lasted longer than a few weeks, trees experienced water stress in spite of growing in wet soils. At wet sites, trees experienced little or no apparent water stress; they remained evergreen or rapidly exchanged leaves during the dry season. In general, the timing of leaf fall and bud break and, in many species, anthesis was determined to a large extent by changes in tree water status. These phenomena, in turn, were a function of the interaction between the water status of the environment and the structural and functional state of the tree. At times the functional state of the tree would counteract the environmental influences; trees with growing shoots experienced temporary water deficits during the wet season, and bare trees rehydrated during drought. The seasonal pattern of tree development had a high correlation with seasonal variation in tree water status, but only indirectly with environmental water availability. No evidence was found for the control of tree development by seasonal variation in photoperiod or temperature.